Scholar profile: Alex Nixon

Multi-species cover cropping is the most effective way to improve soil health, and has the potential to reverse damage caused by years of conventional, full tillage farming practices and boost the sustainability of broadacre dryland cropping in Australia.

A report released today by 2017 Nuffield Scholar, Alex Nixon, collates global research on sustainable farm management practices and reveals that by using cover crops, farmers can greatly increase the health of their soils.

Supported by the Grains Research and Development Corporation (GRDC), Mr Nixon used his Nuffield Scholarship to research the use of cover crops around the world and develop a blueprint for the adoption of the emerging land management practice back home.

Mr Nixon runs an 8,500-hectare cattle and cropping operation near Roma, Queensland. As the third generation of his family to farm the land, and with a young family of his own, a desire to leave his property in better condition for future generations motivated his research.

Acknowledging that cover cropping in the Australian broadacre sector to date has been largely based on single species crops, the report reveals that multi-species crops are more beneficial because they avoid the presence of a monoculture and boost microbial diversity and activity.

“Single-species cover crops do enhance ground cover, but by adding even one or two different species into a cover crop the microbial activity can be greatly enhanced, boosting the diversity of the soil ecosystem,” he said.

Mr Nixon’s research goes beyond the raw benefits of multi-species cover cropping, to explore the viability of the practice in an Australian context.

“Despite the benefits, a number of barriers to adoption remain for Australian farmers,” he said.

“Upfront costs can be an issue. Cover crop seed is very expensive, as is the investment required for machinery or contract sowing.

“Visiting farms in the United States and England, it was clear that the initial cover cropping season can result in some financial deficits. At Overbury Farms in England, long-term soil conservation had been prioritised over the short-term bank balance, and lower income was being supplemented by other revenue streams.”

Mr Nixon’s report recommends that Australian growers looking to implement a multi-species cover crop regime start small, and consider the frequency and size of cover rotations based on the benefits they can produce.